1. Technical Field
The present disclosure relates to a semiconductor light source driving apparatus that supplies a current to drive series-connected semiconductor light source elements.
2. Description of the Related Art
Unexamined Japanese Patent Publication No. 2009-295791 discloses a semiconductor light source driving apparatus that has a plurality of driving circuits. Each of the driving circuits has a current regulating circuit, a light emitting diode (LED), and a voltage detector. The current regulating circuit includes an operational amplifier, a current detecting resistor, and a field effect transistor (FET). The LED is connected between a power source and a drain of the FET. The voltage detector detects a voltage applied across the LED. The semiconductor light source driving apparatus adaptively controls a power source voltage based on a voltage applied to each of the LEDs to increase power efficiency.